Each vehicle that is approved for driving on public roads, especially passenger cars and trucks, requires a service brake for braking a vehicle as well as a parking brake to prevent the vehicle from rolling away when at a standstill. With vehicles that have a manual transmission, it is known to design the parking brake as a so-called handbrake which is activated by means of a manually actuated parking lever. The parking lever is normally provided with a releasable blocking mechanism to fix the parking lever in at least one parked position, generally in the form of a ratchet-like locking mechanism. A button is provided at the end of the parking lever to release the blocking mechanism.
In the case of motor vehicles with an automatic transmission, a parking lock is additionally provided which can be engaged by means of the gear shift lever when the motor vehicle is at a standstill and, in addition to the parking brake, secures the vehicle from rolling away. The parking lock is disposed in the central drive train of the motor vehicle between the engine and wheel axles.
In the case of electric vehicles with a wheel hub drive, there is no central drivetrain, and hence only a certain amount of drag torque is provided by the electric motor in an electric vehicle. However, a disadvantage is that the drag torque of the electric motor is only sufficient to prevent the vehicle from rolling away on a substantially flat area.